1. Field of the Invention
The present invention relates to a lane separation line detection correcting device and a lane separation line detection correcting method, which are used upon automatic control of a steering angle of a vehicle so that the vehicle is may be prevented from departing from a driving lane when the vehicle has almost departed from the driving lane during traveling, and to an automatic driving system including the lane separation line detection correcting device.
2. Description of the Related Art
Hitherto, there has been a technology for detecting a position, an inclination, and a curvature of a lane separation line, which is represented by a white line, based on image information taken by a camera, and for automatically controlling the steering angle of a vehicle by using the detected position, inclination, and curvature so that the vehicle may not depart from a driving lane, as seen from e.g. Japanese Patent Application Laid-open No. 2015-197794.
However, the image information taken by the camera is greatly influenced by the surrounding environment, such as road surface glare from the sun, the lights of an oncoming vehicle, shadows on the road surface, paint, etc. As a result, when the position, inclination, and curvature of the lane separation line are detected in the environment that is constantly changing during traveling, accuracy of the detection often deteriorates.
In particular respect of the lane separation line, there is a need to detect the curvature far away. In such a case, a phenomenon may occur in which the curvature is detected as being several times larger than that of the actual road shape due to an erroneous detection caused by obstruction to the curvature detection by a preceding vehicle, an oncoming vehicle, etc. At the time when the steering angle of the vehicle is automatically controlled by using overestimated curvature information resulting from that erroneous detection, there is a problem in that the behavior of the vehicle becomes unstable.